1. Field of the Invention
The present invention relates to indicating devices and more particularly to an indicating device displayed in an automobile, indicating to the driver the direction of motion to align the automobile with a trailer hitch.
2. Description of the Prior Art
The use of trailers to expand the capacity of an automobile has gained wide acceptance amongst the public. One of the difficulties in using a trailer is during coupling, when close alignment of the automobile relative the trailer has to be made. This alignment is made by backing up the automobile towards the trailer until the draw bar aligns with the trailer hitch. The location of the draw bar, however, is typically obscured from view by the trunk of the automobile and the hitch alignment is therefore similarly obscured during the last stages of approach. Thus, the driver either has to seek assistance from another person to guide him into alignment, or has to make repeated tries until eventually a successful alignment is made.
Typically, a trailer is provided with a tongue extending from the frame thereof which terminates in a hitch adapted to engage a ball attached to the draw bar which, in turn, is mounted to the frame of the automobile. When heavy loads are coupled it is this alignment of the ball relative to the hitch that requires a close match-up. Because of the usual frame attachment, however, the ball itself is not visible to the driver.
In the past there have been many devices developed to assist the driver in this alignment. Most often such devices are in the form of mirrors which provide the driver with direct view of the ball. The use of mirrors, however, reverses the viewing orientation with the result that the driver becomes disoriented or has to learn new habits of response. Alternatively there have been devices developed which, by way of feelers, provide to the driven an indication of the proximity of the hitch. Again, such feelers only provide a coarse indication and only at a limited point in the approach. Thus, outside of the range of the feelers the driver has no indication at all and again has to rely on third party assistance or on repeated tries.